games/robots/rnd_pos.c

   1 /*-
   2  * Copyright (c) 1980, 1993
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. Neither the name of the University nor the names of its contributors
  14  *    may be used to endorse or promote products derived from this software
  15  *    without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  *
  29  * @(#)rnd_pos.c        8.1 (Berkeley) 5/31/93
  30  * $FreeBSD: src/games/robots/rnd_pos.c,v 1.5 1999/11/30 03:49:20 billf Exp $
  31  * $DragonFly: src/games/robots/rnd_pos.c,v 1.3 2006/08/27 21:45:07 pavalos Exp $
  32  */
  33
  34 #include "robots.h"
  35
  36 #define IS_SAME(p,y,x)  ((p).y != -1 && (p).y == y && (p).x == x)
  37
  38 static int rnd(int);
  39
  40 /*
  41  * rnd_pos:
  42  *      Pick a random, unoccupied position
  43  */
  44 COORD *
  45 rnd_pos(void)
  46 {
  47         static COORD pos;
  48         static int call = 0;
  49
  50         do {
  51                 pos.y = rnd(Y_FIELDSIZE - 1) + 1;
  52                 pos.x = rnd(X_FIELDSIZE - 1) + 1;
  53                 refresh();
  54         } while (Field[pos.y][pos.x] != 0);
  55         call++;
  56         return &pos;
  57 }
  58
  59 static int
  60 rnd(int range)
  61 {
  62
  63         return random() % range;
  64 }